As shown in the video, we got a size small backpack with the husky stuffed animal. My son is wearing the backpack and is 20 months old and ~28 pounds. It's a really nice fit and sufficient storage space for 2 books, 2 koosh, and other miscellaneous toys that he packed when going to grandma and grandpas house. He loves the stuffed animal - regularly gives "Blizzard" hugs - and has no trouble using the zippers.